It was a fitting end to an awesome serving display. And there couldn't have been a more fitting successor to Pete Sampras as U.S. Open champion.

With 23 aces, strong baseline play and a veteran's composure, Roddick beat Juan Carlos Ferrero 6-3, 7-6 (2), 6-3 Sunday, a breakthrough victory that very well could be followed by a series of major triumphs.

''I can't imagine my name and 'U.S. Open champion' together. It's more than I could ever dream of,'' Roddick said. ''I came to this tournament so many times as a little kid and watched from way up there.''

He's still a kid, of course, just 21. And the newly No. 1-ranked Ferrero is 23, making for the youngest combined ages of U.S. Open finalists since Sampras beat Andre Agassi in 1990.

After Roddick's final too-fast-to-see serve his 123rd ace of the tournament he curled into a ball, covering his eyes as they welled with tears. Then he waded through the courtside photographers' pit and climbed into the stands for a frenzied series of hugs with his singer-actress girlfriend, Mandy Moore, his parents, his brothers and a couple of friends who drove 10 hours to cheer on their buddy.

It was an uplifting end to a rain-soaked Open with scheduling problems that forced Ferrero to play four matches in four days, the first time in the 35-year Open era that's happened at a major.

The Open began two weeks ago with a retirement ceremony in Arthur Ashe Stadium for Sampras, who beat Roddick in the quarterfinals last year en route to his record 14th Grand Slam title. And Sunday's performance on the same court allowed Roddick to strut into the postmatch news conference and announce: ''No more, 'What's it feel like to be the future of American tennis?'''

''I don't think you could have written a script any better, with Pete's retirement,'' Roddick said. ''It was just too good.''

Men's tennis has been as wide open as ever lately: Roddick is the eighth man to win at the last eight Grand Slam tournaments, tying the Open era record for most consecutive different champions.

But Roddick appears to have staying power. He's won 19 straight matches, and is 37-2 since teaming with coach Brad Gilbert, Agassi's former mentor, after a first-round exit at the French Open.

''There's been a lot of pressure on him. This will shut a lot of people up that he was all hype,'' U.S. Davis Cup coach Patrick McEnroe said. ''We knew he had it. It's a great day for him and for American tennis. It's a great passing of the baton.''

Roddick rises to a career-best No. 2 in the rankings and now leads the tour with six titles in 2003.

The most important one, of course, is the most recent, a championship at the U.S. Open to put alongside the junior title he won at the National Tennis Center only three years ago. Stefan Edberg is the only other person with boys' and men's Open titles.

''I'm baffled by how calm I felt out there and how easy it was,'' Roddick said. ''I almost didn't feel anything out there.''

Perhaps most impressive was his ability to hang in there on long rallies with French Open champion Ferrero, a consummate baseliner who beat Agassi relatively easily in the semifinals. In contrast, Roddick's biggest test came in Saturday's semis, where he trailed 2-0 in sets and faced a match point before beating No. 13 David Nalbandian.

''Yesterday was a different climate. The other guy was returning and playing well,'' Gilbert said. ''Andy played not to lose yesterday, and today he played to win.''

Ferrero was out on a practice court in the shadow of the stadium 2 1/2 hours before the final's start, getting some last-chance work on returning serves. To replicate the power Roddick produces, Ferrero's coach told his hitting partner to move up about 3 feet inside the baseline to serve.

During his warmup, meanwhile, Roddick loosened up by using his racket as though it were a baseball bat, taking cuts with a two-handed backhand and trying to hit balls over the fence. A bemused Ferrero looked on, sipping an energy drink.

Once the action began for real, Ferrero was often reduced to bystander.

It wasn't just that Roddick smacked serves that would be fined for speeding on a European highway. He also has mastered the art of placement.

''Today I didn't play my best tennis,'' Ferrero said, ''but Andy played so good, and he served unbelievable, and I couldn't do much.''

If the Spaniard was listless, he had an excuse (one he didn't use). Roddick was playing for a third straight day, because his fourth-round match ended Wednesday, a day earlier than Ferrero's.

Ferrero did look out of sorts at times, including when he forgot he had to switch sides of the court after the opening game of the second set. He wasn't moving his feet well, and that's one of the keys to his game he earned the nickname ''Mosquito'' for the way he zips around the court.

Even when Ferrero did show spunk, Roddick had an answer.

On the opening point of the tiebreaker, Ferrero used a flat-out dive to his left for a stinging backhand volley. But as he was rising and gathering himself, Roddick spun a forehand passing winner.

Ferrero then hit a brilliant winner, running so far he ended up against the stands, and a Roddick error made it 2-1 for the Spaniard. But Roddick reeled off six straight points to take the set, ending it with a crosscourt forehand winner that Ferrero simply gave up on.

Roddick never was broken, though he actually faced a break point in the third game of the afternoon. He saved it with a 135 mph serve that drew a long return. Roddick then picked up the only break of the first two sets in the very next game.

He got to break point when his backhand return clipped the net and landed deep, forcing an awkward forehand by Ferrero that landed wide. And Roddick took a 3-1 lead with a crosscourt forehand winner to the corner.

Roddick lost the second point of the ensuing game, then began a run of 23 straight points on his serve. That included the final game of the first set, which Roddick won this way: forehand winner down the line, 139 mph service winner, 141 mph ace, and 131 mph ace.

He didn't celebrate, though. He just calmly walked to his seat while the partisan crowd gave him a standing ovation.

''I'm baffled by how calm I felt out there. How easy it was,'' Roddick said. ''I almost didn't feel anything.''

He used to be known for on-court antics, from tossing rackets as a junior, to a tantrum in his quarterfinal loss to Lleyton Hewitt at the 2001 Open, to slapping high-fives with fans after a point here last year.